U.S. patent number 7,144,331 [Application Number 10/966,374] was granted by the patent office on 2006-12-05 for metal wood.
This patent grant is currently assigned to Acushnet Company. Invention is credited to Raymond L. Poynor.
United States Patent |
7,144,331 |
Poynor |
December 5, 2006 |
Metal wood
Abstract
A substantially hollow body metal wood golf club head has a wrap
around insert that comprises a substantial portion of the front
face. The insert having a wing-like extension that extends around
the heel portion of the club head and a pre-determined distance of
about 0.657 inch into the skirt portion of the club head. A gap of
about 0.06 inch to about 0.36 inch is created between an internal
thru-hosel and the interior wall of the heel. The gap represents
material and weight that may be used more effectively in other
parts of the club head. The lack of connection between the hosel
and the front face creates a greater unsupported front face and
therefore a greater "sweet spot" area.
Inventors: |
Poynor; Raymond L. (Oceanside,
CA) |
Assignee: |
Acushnet Company (Fairhaven,
MA)
|
Family
ID: |
36181484 |
Appl.
No.: |
10/966,374 |
Filed: |
October 15, 2004 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20060084523 A1 |
Apr 20, 2006 |
|
Current U.S.
Class: |
473/305; 473/349;
473/345 |
Current CPC
Class: |
A63B
53/0466 (20130101); A63B 60/00 (20151001); A63B
53/0458 (20200801); A63B 53/0412 (20200801); A63B
53/0408 (20200801); A63B 53/0416 (20200801) |
Current International
Class: |
A63B
53/02 (20060101); A63B 53/04 (20060101) |
Field of
Search: |
;473/324,325,326,342,349,350,305,345,346 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Passaniti; Sebastiano
Attorney, Agent or Firm: Burns; D. Michael
Claims
What is claimed is:
1. A metal wood golf club head adapted for attachment to a shaft
comprising: a substantially hollow cast body and a wrap around
insert; the cast body comprising a crown portion, a sole portion, a
toe portion, a heel portion, a skirt portion connecting the heel
portion to the toe portion, a hosel portion including a hosel tube,
a front face, and an opening defined in the front face for
accepting the wrap around insert; the hosel tube cast as a unitary
part of the body at distance from an internal wall of the body; and
the wrap around insert comprising at least a substantial portion of
the front face, and a wing section extending outwardIy, beneath,
and around the heel portion to a predetermined distance into the
skirt portion.
2. The club head according to claim 1, wherein the distance from a
centerline of the hosel tube to an outer surface of the heel
portion is about 0.3 inch to a maximum of 0.625 inch.
3. The club head according to claim 1, wherein an internal gap
between the hosel tube and the internal wall of the body is about
0.388 inch.
4. The club head according to claim 1, wherein an internal gap
between the hosel tube and the internal wall of the body is about
0.06 inch to about 0.36 inch.
5. The club head according to claim 1, wherein an internal gap
between the hosel tube and the internal wall of the heel portion is
about 0.125 inch.
6. The club head according to claim 1, wherein the wing section has
a width greater than about 10 mm.
7. The club head according to claim 1, wherein the wing section has
a length greater than about 20 mm.
8. The club head according to claim 1, wherein the wrap around
insert is formed from a single stamped titanium plate.
9. The club head according to claim 1, wherein the cast body is
titanium.
10. The club head according to claim 1, wherein the insert is made
of stamped titanium plate.
11. The club head according to claim 10, wherein the insert is of
uniform thickness.
12. The club head according to claim 1, wherein the insert is made
of beta-titanium and is of variable thickness.
13. The club head according to claim 12, wherein the thickness at a
central area of the insert is about 0.13 inch, at the bending area
is about 0.08 inch, and at the distal end of the wing section is
about 0.06 inch.
14. The club head according to claim 1, wherein the wing section
extends a predetermined distance into the skirt portion of at least
about 0.6 inch.
15. The club head according to claim 14, wherein the wing section
extends a predetermined distance into the skirt portion of about
0.657 inch.
16. The club head according to claim 1, wherein the body comprises
a volume range of about 350 to about 460 cc.
17. The club head according to claim 16, wherein the body comprises
a volume of about 420 cc.
Description
FIELD OF THE INVENTION
The present invention relates generally to a metallic hollow golf
club head, and specifically to the placement of a wrapped face
insert having a wing element extending into the heel/skirt portion
of the club body.
BACKGROUND OF THE INVENTION
Golf club "metal woods", were originally manufactured primarily by
casting of durable metals such as stainless steel, aluminum,
beryllium copper, etc. into a unitary structure comprising of a
metal body, face and hosel. As technology progressed it became more
desirable to strengthen the face of the club, and usually this was
achieved by using titanium material.
With a high percentage of amateur golfers constantly searching for
more distance on their drives, the golf industry has responded by
providing golf clubs specifically designed with distance in mind.
The head sizes have increased which allows for the club to possess
a higher moment of inertia, which translates to a greater ability
to resist twisting on off-center hits. However, as a wood head
becomes larger, its center of gravity will be moved back away from
the face resulting in hits flying higher than expected. Reducing
the lofts of larger head clubs is one way to compensate for this.
Also with the larger heads, the center of gravity is moved further
away from the axis that is created by the intersection of the hosel
with the sole plate. This can cause these large head clubs to
remain open on contact, thereby inducing a "slice" effect (in the
case of a right-handed golfer, the ball deviates to the right).
Offsetting the head and incorporating a hook face angle can help
compensate for this by "squaring" the face at impact, but often
more is required to eliminate the "slice" tendency.
The technological breakthrough in recent years towards providing
the average golfer with more distance, by increasing the club head
size, has been to keep the weight constant or even lighter, by
casting consistently thinner shell thickness and going to lighter
materials such as titanium. Also, the club head faces have been
steadily becoming extremely thin. These thinner faces will maximize
what is known as the Coefficient of Restitution (COR), which means
that the more the face rebounds upon impact, the more energy that
may be imparted to the ball, thereby increasing distance. In order
to make the faces thinner, manufacturers have moved to forged or
stamped metal faces which are stronger, in most cases, than those
that are cast. Common practice is to integrate the forged or
stamped metal face by welding it to the body at the sole and crown
transitions. These transitions are the points on the club head that
absorb the greatest amount of stresses as the club strikes the
ball.
A common feature of most metal wood designs that exhibit a
thru-hosel construction is that there is an intimate connection
between the face, hosel tube and heel portion of the skirt wall.
This often results in a reduced unsupported face area due to a
narrower supporting perimeter, thereby reducing the overall face
flexibility and "sweet spot".
Therefore, it is very desirable to provide a method for attaching
the impact face portion to the body of the club head without
sacrificing any COR (Coefficient of Restitution) value or "sweet
spot" size.
SUMMARY OF THE INVENTION
In accordance with one aspect of the invention, a metal wood golf
club head is provided which includes a hollow body having a wrap
around insert welded to the front face. The body is preferably cast
as a single member and includes a sole portion, a crown portion, a
front face, a toe portion that extends into the impact area of the
front face portion, a heel portion, a skirt portion connecting the
heel portion to the toe portion, a hosel portion comprising an
internal thru-bore hosel tube, and an opening defined in the front
face for receiving the wrap-around insert. The wrap around insert
forms a substantial portion of the impact face of the club, and has
at a distal end a wing section extending around and beyond the
hosel tube and into the body at the heel/skirt area of the club.
The distance the wing section extends into the skirt portion is at
least 0.60 inch, and preferably about 0.657 inch.
In the invention a stamped plate is used for the wrap around
insert, and since a stamped plate made of beta-titanium generally
exhibits better strength and ductility properties than cast
titanium, it is preferable to use it as a substantial portion of
the impact face of the front section. It is appreciated that in the
joining of the insert to the front face of the body, the welding is
removed away from the crown/face and sole/face transition seams,
which are points of critical stress. The present invention provides
for these welds to be done a distance away from the transition
seams, thereby keeping the thickness at the transitions much
thinner than if welds were present. This increases the structural
integrity of the club head and also achieves maximum allowable COR
values.
In the invention, the wrap around design of the insert provides the
ability to increase the club head volume behind the plane of the
hosel, without having to add material and overall weight to
maintain the connection between the hosel tube and adjacent skirt
wall. The result of this is a larger unsupported face area and in
addition to increasing the hitting area "sweet spot", it allows for
more discretionary weight to be available to further optimize the
mass properties of the club head, which is one of the key elements
for achieving ideal launch conditions and overall performance.
The wrap around feature of the insert creates a gap of about 0.3
inch to about 0.625 inch between the hosel tube and the wall of the
heel portion.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of the club head body of the present
invention showing the hosel tube and an opening in the body.
FIG. 2 is a front view of the thru-hosel design.
FIG. 3 is a heel elevation view showing the opening as it extends
into the skirt section to accommodate the wrap around insert.
FIG. 4 is a front elevation view of the wrapped face insert.
FIG. 5 is a top view of the insert of FIG. 4.
FIG. 6 is a partial cross section bottom view taken along line B--B
of FIG. 4.
FIG. 7 is a partial cross sectional toe view along lines A--A of
FIG. 4.
FIG. 8 is a heel view of FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the present invention, as shown in FIGS. 1 8, there is
provided a golf club head 20, adapted for attachment to a golf club
shaft, which for the sake of clarity, is not shown. Club head 20 is
integrally formed by coupling the edges of a wrap-around metal
insert 40, to a substantially hollow body 21 so as to form a cavity
22 therein. The preferred means for coupling is welding.
Body 21 is preferably cast of a titanium alloy. It may also
comprise materials such as stainless steel, aluminum or composites.
Body 21 includes a crown portion 23, a heel portion 24, a toe
portion 25, a sole portion 26, a front face 27, a skirt portion 28
connecting the heel portion 24 to the toe portion 25, a hosel
portion 29 comprising a hosel tube 30, and an opening 31 defined in
the front face 27 of a size and shape for receiving the wrap around
insert 40. The hosel tube 30 has a centerline C/L that intersects
the sole portion 26, and the heel portion 24 has an outer surface
line H/L.
As shown in FIGS. 4 8, the wrap around insert 40 includes an impact
face 41, an upper edge 42, a lower edge 43, and a wing section 44
for extending outwardly into the skirt portion 28 and also below
and beyond the hosel tube 30. Wing section 44 has a length y that
is preferably greater than about 20 mm, and a width w that is
preferably greater than 10 mm. Insert 40 is preferably made of
stamped titanium plate, more preferably beta-titanium and may be of
variable thickness.
The present invention, by incorporating the aforementioned wing
section 44 into body 21, enables weight that is normally used in
the hosel area, to be placed elsewhere in the club head 20 for
optimum ball flight. The preferred size of the present invention
club head is about 420 cc club head, and that size yield a savings
of at least about 6 grams of material which can be then positioned
at another location in the club head for improved performance.
The design of the cast body 21, in which the toe portion 25, crown
portion 23 and sole portion 26 form part of the front face 27, is
such that welding of these portions to the insert 40 is kept a
relative distance away from the transition seams formed by those
portions. This increases the stability of the cast body 21 during
manufacture and also insures minimum deformation of the
aesthetically critical toe portion 25 during welding or polishing.
The welding engagement along the perimeter of the insert 40 shifts
the weld zone away from the critical crown/face and sole/face
transition seams, therein reducing the thickness at the seams; this
is a vital parameter in maximizing COR value. Beta-titanium and
Alpha-titanium materials are preferred in the impact face 41 of the
insert 40 because of superior mechanical properties, such as
strength and ductility.
Although the size of conventional face inserts varies from one
design to another, one common feature that these constructions have
is an intimate connection between the face, hosel tube, and heel
portion of the skirt wall. This results in a reduced unsupported
face area if a narrower supporting perimeter was utilized. This can
also potentially reduce the overall face flexibility and sweet
spot. The wrapped face insert 40 of the present design eliminates
all interior connections with the front face portion 27, thereby
maximizing the unsupported face area and allowing greater
opportunity to increase the hitting area sweet spot. One notable
improvement in the design of the wrap around insert 40 is the
ability to increase the volume of the club head 20 behind the hosel
plane, by eliminating material, and therefore overall weight, that
has been necessary to maintain the connection between the hosel
tube 30 and adjacent skirt wall 28. This results in a larger face
area and more discretionary weight available to further optimize
the mass properties of the club head 20, which is a key aspects
towards achieving ideal launch conditional and overall
performance.
As previously stated, the design of the wrap around insert 40
facilitates the removal of undesirable weight that is positioned
between the internal hosel tube 30 and the skirt wall directly
adjacent the hosel tube 30. Prior art cast body construction of any
metal wood club head, when coupled with the thru-bore hosel design,
usually requires a connection between the hosel tube and the
adjacent skirt wall due to the complexity and manufacturability of
a collapsible core that creates the hollow cavity. The present
design utilizes the wrap around insert 41, which extends into and
wraps around the heel portion of the face/skirt junction, thereby
allowing access behind the hosel tube 30. This additional access
behind the internal portion of the hosel tube 30 provides the
clearance needed to increase the core volume to a point where is
fully extends behind the hosel tube 30, yielding a hollow area
where there once was unwanted material and added weight.
The wing section 44 extends into and engages the skirt portion 28
at a pre-determined distance. In a preferred embodiment, the
predetermined distance x is at least 0.6 inch and preferably about
0.657 inch, as measured from the front center portion of the insert
40 to the edge 46 of the wing section 44. The insert 40 is attached
to the body 21 generally by welding along an engagement line
45.
As described above, the wrapped face insert 40 may be preferably
formed from a single stamped metal sheet plate, as shown in FIGS. 4
8, and may be of uniform thickness, but preferably is of a varied
thickness with a wing section 44 formed by bending of the sheet
metal. The thickness T1 at the central portion of the insert 40 is
about 0.13 inch; and at the bending area the thickness T2 is about
0.08 inch, wherein it then tapers to a thickness T3 of about 0.06
inch, preferably about 0.057 inch, at the distal end of the wing
section 44.
As stated above, the insert 40 attaches into the skirt junction of
the body to create a gap 46 between the hosel tube 30 and the
internal wall at the heel. The gap 46 is accessible only because
the insert 40 wraps around the heel section of face and skirt
junction. The distance CD between the hosel bore centerline C/L and
the adjacent outer surface of the heel is in a range between about
0.3'' to 0.625'', and preferably about 0.388 inch for the present
invention. The width GD of the gap 46 which is created between the
hosel and the internal wall, is in a range between about 0.06'' to
about 0.36'', and preferably about 0.125'' for the present
invention. Presently, the USGA rules App. 11 1d.ii indicates that
the maximum distance allowable between the hosel bore centerline
C/L and the adjacent outer surface of the heel is 0.625 inch.
While various descriptions of the present invention are described
above, it should be understood that the various features of each
embodiment can be used singly or in any combination thereof.
Therefore, this invention is not to be limited to only the
specifically preferred embodiments depicted herein. Further, it
should be understood that variations and modifications within the
spirit and scope of the invention may occur to those skilled in the
art to which the invention pertains. Accordingly, all expedient
modifications readily attainable by one versed in the art from the
disclosure set forth herein that are within the scope and spirit of
the present invention are to be included as further embodiments of
the present invention. The scope of the present invention is
accordingly defined as set forth in the appended claims.
* * * * *